(Adapted from the Applicant's Abstract) This core will provide the cell culture, DNA isolation and mapping support for the projects and cores in this SCOR. The routine activities of this core will include the following. The core will establish lymphoblastoid cell lines from patients with congenital heart defects; isolate DNA from established cell lines, blood spots or cheek swabs; pre-screen patients with conotruncal anomalies for a 22q11.2 deletion by PCR; FISH verify 22q11.2 deletions in at-risk patients until a quantitative PCR assay is developed by Project 1; assess biparental inheritance status by PCR; map newly identified human cDNAs to their respective chromosome by PCR or Southern hybridization analysis of a panel of somatic cell hybrid DNAs; regionally localize new human cDNAs by FISH; map newly identified mouse cDNAs to their respective mouse chromosome by utilization of the Jackson Laboratory Backcross DNA Mapping Resource; and provide access to large genomic fragments of DNA from the CEPH YAC library utilizing published YAC maps and BAC/PAC clones from on-site resources.